The lab procedure mentions that not all of the oxone may dissolve after being added to the water because the water may be saturated. Which statement best explains this:

(A) There are less solute molecules than water molecules.

(B) The amount of dissolved solute is the same as the amount of undissolved solute.

(C) There are more solute molecules than water molecules.

(D) The system is in dynamic equilibrium.

The answer is (C) There are more solute molecules than water molecules.

Explanation:

A saturated solution is one in which no more solute can be dissolved or disintegrated into the solvent. When or if the ozone stops being dissolved in the water, it implies that the water has already taken on more ozone molecules than it can contain, meaning there are more solute molecules (ozone molecules) than there are solvent molecules (water molecules).

(D) The system is in dynamic equilibrium.

Explanation:

Chemical reactions can either go in both directions (forward and reverse) or only in one direction. The ones that go in two directions are known as reversible reactions, and you can identify them by the arrows going in two directions, like the example below.

H2O (l) ⇌ H + (aq) + OH - (aq)

Dynamic equilibrium only occurs in reversible reactions, and it's when the rate of the forward reaction is equal to the rate of the reverse reaction. These equations are dynamic because the forward and reverse reactions are still occurring, but the two rates are equal and unchanging, so they're also at equilibrium.

Dynamic equilibrium is an example of a system in a steady state. This means the variables in the equation are unchanging over time (since the rates of reaction are equal). If you look at a reaction in dynamic equilibrium, it'll look like nothing is happening since the concentrations of each substance stay constant. However, reactions are actually continuously occurring.

Dynamic equilibrium doesn't just occur in chemistry labs though; you've witnessed an dynamic equilibrium example every time you've had a soda. In a sealed bottle of soda, carbon dioxide is present in both the liquid/aqueous phase and the gaseous phase (bubbles). The two phases of carbon dioxide are in dynamic equilibrium inside the sealed soda bottle since the gaseous carbon dioxide is dissolving into the liquid form at the same rate that the liquid form of carbon dioxide is being converted back to its gaseous form.

The equation looks like this: CO2 (g) ⇌ CO2 (aq).